I designed it to make maintenance easier. The venturi valve is for dosing, the tap is for extracting sample water for testing, the 2 valves on the fresh saltwater supply line are so i can close off that long pipe while mixing so no salt or unmixed water gets into the pipe and become stagnant, and the valve at the other end is so i can control the new water coming into the tank to prevent any overflows. There are a couple bypasses in the supply line incase a piece of equipment is down i can maintain circulation in the tank.